SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26b42b14d5d1045266a6550ab174a1d4f7bfab2068bb8bc81276b240b4c94bfd' 
  AND token = 'iUpl/usNbqzZ1uQUrKYdsm+Nq4vKMHRqrIx5/xM/shw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}